Newbies, ignore Metal Halide. Read why. Experienced growers do what the fuck ever you want. Including wasting money.
• HPS is about twice as electrically efficient as metal halide.
• Photosynthetically Active Radiation (PAR) is what really matters to plant growth, and delivery of usable PAR is better with HPS than metal halide.
• The enhanced blue in metal halide does not lead to increased plant growth compared to HPS in the “veg” stage.
• Metal halides deliver, on average, about 80,000-110,000 lumens per standard 1,000-watt bulb. For the same wattage, HPS bulbs delivers about 130,000-155,000 lumens. This increased light output far outweighs other considerations when trying to maximize plant growth
https://www.marijuanaventure.com/metal-halide-vs-high-pressure-sodium-age-old-question-cannabis-grower